The present invention relates to a water filtration apparatus for mounting on the exposed or visible exterior surfaces of a refrigerator. More specifically, the present invention is an apparatus with a readily replaceable filter cartridge for providing filtered water to the interior of a refrigerator cabinet so that filtered water is available for the refrigerator""s ice maker or chilled water dispenser.
Water intended for human consumption is expected to be either free of harmful constituents or contain concentrations of such constituents that are below harmful levels. To provide potable water for use in homes and businesses, municipalities utilize industrial scale processes in an effort to eliminate or reduce harmful constituents present in water drawn from large, naturally occurring water sources. Potable water is also frequently obtained on a smaller size scale from wells and springs and usually without any treatment prior to consumption.
Unfortunately, the potability of a particular water supply is sometimes questionable. The consistency and efficiency of treatment by municipalities may vary due to numerous factors such as heavy rainfall, equipment failures, and usage levels. Depending upon the seriousness of a variation in treatment, a municipality may be forced to notify its consumers that further treatment of the water supplied, e.g. boiling, is required at the point of use before consumption is safe. Water obtained directly from a natural source may also become suspect depending upon environmental conditions near the source. For examples, wells and springs can be contaminated due to rain water run-off washing a contaminant into the source.
Various water filtration devices have been developed. Such devices range from those located at the point-of-use (e.g. the spigot of a kitchen sink, gravity-flow dispensers such as dispensers, and low-pressure dispensers such as sports bottles) to the generally bulkier point-of-entry units hidden from view within the plumbing of a home or office. Many of these devices use activated charcoal in at least one stage of the filtration process. Activated charcoal helps to remove strong odors and tastes from water. More specifically, activated charcoal can remove chlorine and sediment from water.
Generally, the currently available devices for water filtration on a nonindustrial scale may be divided into two categories: point-of-use and point-of-entry filtration systems. Typically, a point-of-entry system provides for the filtration of water at the point where the supply enters a dwelling or area of use. The point-of-entry system filters the entire water supply, and filtered water is then distributed to various points of use after filtration. As an example, a point-of-entry system may be located in the basement, cellar, or other location hidden from plain view. In contrast to point-of-use systems, point-of-entry systems may be larger in physical size because of the volumetric rate of water that must be filtered in order to supply filtered water to all of the points-of-use within a dwelling or other use area. Furthermore, a point of entry system may be less efficient because water may be filtered unnecessarily. For example, the homeowner may desire filtered water for the kitchen and bathrooms but not for outdoor spigots or laundry.
Point-of-use systems, on the other hand, provide for filtration of the water at the point of consumption or application. For example, point-of-use systems may be located at the kitchen sink ensuring that potable, filtered water is used in cooking and kitchen cleaning. Such systems may consist of a device, visible to the user, attached to the end of a faucet. Other systems may consist of a filter located within a pitcher such that water placed into the top of the pitcher filters water through to a bottom compartment for storage until consumption. Still other systems, due to size and bulkiness, may be located under a sink or within a nearby kitchen cabinet.
Point-of-use water filtration systems for refrigerators have also been developed as automatic ice-makers and chilled water faucets or dispensers are now common features on many of the commercially available models. For those consumers not having point-of-entry systems, the water must be filtered prior to ice formation or water dispensing if unwanted contaminants are to be removed before use. Point-of-use filtration systems for use in conjunction with household refrigerators are varied as described below.
For example, U.S. Pat. No. 5,320,752, issued to Clack et al., describes a water purification system employing a modular flat filter assembly for installation inside a freezer door, beside a kitchen cabinet, or on a countertop. The U-shaped filter housing is charged with a granulated filtration medium such as activated charcoal. The filter housing has a plurality of staggered ribs and protrusions formed in the walls of the housing. These features allegedly provide structural support against water pressure within the filter housing and prevent flow channels from forming in the granulated filtration medium. While the filter assembly is described as flat, the use of granular filter media, staggered ribs, and protrusions add bulk and thickness to the filter assembly. Furthermore, the unit is not intended for mounting on the exterior surfaces of the refrigerator where the filter media may be readily accessed and replaced when necessary. Instead, like other point-of-use water filtration systems used in conjunction with refrigerators, the filtration apparatus is difficult to reach and access without moving the refrigerator or opening the refrigerator/freezer doors.
U.S. Pat. No. 3,982,406, issued to Hanson et al., illustrates a refrigerator water storage dispensing system with water filter. The system includes a water storage tank and a filter cartridge assembly that are installed within the interior of a refrigerator for removing undesired constituents from the chilled water stream immediately prior to being dispensed. The filter media is contained within a cartridge constructed from an elongated hollow cylindrical casing or tube. The filter container is described as having an overall height of 13 inches and is filled with a granular material such as granular activated charcoal. The system occupies a substantial amount of space within the interior of the refrigerator cabinet because it requires a location for both the water tank and the filter cartridge. In addition, the filter cartridge is not readily accessible for replacement of the filter media because the cartridge is located within the interior of the refrigerator cabinet and must be accessed by opening the doors to the refrigerator and relocating any food products that might interfere with such access.
U.S. Pat. No. 4,207,994, issued to Offlee, describes a refrigerator system utilizing assemblies to enable dispensing cold water or ice made from purified water. The system consists of a cabinet located near the refrigerator containing a water tank, pump, and filter that is connected by piping to the refrigerator. Another tank may be located within the refrigerator for water storage. When the water level in the refrigerator tank falls below a certain level, the pump is activated and filtered water is pumped from the cabinet into the tank within the refrigerator. Water in the cabinet tank may be passed through a filter and then to the pump. Alternatively, the cabinet tank may be stocked with water that has already been filtered such that no filter is required for the cabinet. This system requires a substantial amount of space near the refrigerator for locating the cabinet. Unlike the present invention, the filter is not located on the exterior of the refrigerator or the cabinet where filter replacement may be more readily facilitated. In addition, this system requires a pump which must be powered and eventually replaced when worn.
U.S. Pat. No. 4,571,953, issued to Caruso, describes a combined refrigerator and water filtration unit. While the filtering apparatus is not specified, chambers for holding a water filtration apparatus are located within the refrigerator compartment. The chambers are illustrated as two large cylinders located within the compartment. As with the other devices described above, the chambers described in U.S. Pat. No. 4,571,953 are not readily accessible for easily changing the filter media. In addition, the water filtration units appear to occupy a large volume of the refrigerator cabinet.
U.S. Pat. No. 5,135,645, issued to Sklenak et al., is a directed to a refrigerator water filter located in a compartment constructed within the wall of the refrigerator cabinet. A small cover is used to access the filter from the inside compartment of the refrigerator. The filter is illustrated as a cylindrical cartridge. Because of its location within a compartment constructed in the refrigerator wall, the filter media cannot be readily replaced or observed without first opening the refrigerator door and removing or relocating refrigerated items in front of the compartment.
U.S. Pat. Nos. 5,290,442; 5,454,944; and 5,560,393, all issued to Clack, describe a self-contained, purified drinking water refrigerator storage apparatus. A filter assembly is attached to the rear of a water storage container. Means are provided for attaching the apparatus to a faucet. Upon turning on the faucet, water flows through the filter assembly and into the storage container. Once the container is full, the water storage apparatus is disconnected from the faucet and placed into a refrigerator for storage until consumption. As defined, provision must be made for the space occupied by the container and the cylindrically-shaped filter cartridges on the back of the container. Furthermore, replacement of the filter media requires disconnecting tubing from the filter cartridges.
U.S. Pat. Nos. 5,707,518 and 5,715,699, all issued to Coates et al., describe a refrigerator water filter assembly for mounting onto the surfaces of the interior of a refrigerator. The filter cartridge includes a cylindrical filter media located within a housing that is mounted inside the refrigerator. Accordingly, the filter media cannot be replaced or observed without opening the refrigerator door and relocating items near the filter. Additionally, removal of the filter media for replacement requires that a housing be unscrewed and the filter cartridge removed from the housing.
A common deficiency of previous devices for filtering water for refrigerator units is the difficulty of accessibility to the device. Most of the devices discussed above are filtration units that are mounted either inside the refrigerator, inside the refrigerator cabinet shell, or on the rear, unaccessible exterior of the refrigerator. By being mounted in such locations, the filtration units is not easily observable for the purpose of determining when the filter media in the device has reached the end of its useful life. In addition, replacing the filter media is difficult because either the refrigerator doors have to remain open during replacement and stored items must be relocated, or the entire refrigerator must be pulled away from the wall to gain access to the rear exterior. Therefore, there is need for a water filtration apparatus, for use with a refrigerator, that can be readily observed to determine when the filter media is spent and that can be accessed to facilitate filter removal and replacement with a clean filter. Optimally, a need exists for an apparatus that meets these needs while occupying only a minimum amount of space.
The present invention addresses some of the problems identified above by providing a water filtration apparatus for mounting on the exposed exterior surfaces of a refrigerator. A means of mounting the apparatus onto the exterior surfaces is provided. The apparatus also includes a readily replaceable filter cartridge. Due in part to these features, the water filtration apparatus of the present invention results in improved efficiency in replacement time and required space as compared to existing devices. The inventive device also results in an apparatus that is readily observable to determine whether the filter media has reached the end of its useful life.
To enable the filter cartridge to be readily replaceable, the filter cartridge is releasably connectable, without the use of special tools, to a filter receptacle. The filter cartridge contains a material or combination of materials for removing undesired constituents from the unfiltered water. Because of the ease with which the filter cartridge of the present invention may be replaced and further because of its readily accessible location on the exterior of the refrigerator, the volume of filter media required may be reduced, which allows the overall size of the present invention to be smaller than existing devices. The size may also be reduced through the use of a flat water filter media. Available in sheets that are less than xe2x85x9 inches in thickness, flat water filter media may be used within the filter cartridge of the present invention to substantially reduce its overall size as compared to existing refrigerator water filters that employ a granular filter media in filters that are not as easily accessible.
To use the water filtration apparatus of the present invention, the consumer mounts the housing containing the filter cartridge onto the exterior surface of the refrigerator. An unfiltered water supply is connected to the unfiltered water inlet of the present invention. Water from the unfiltered water inlet flows to the filter receptacle and through the filter media. Filtered water exits the filter media and is supplied to the refrigerator through a filtered water outlet that the consumer connects to the interior of the refrigerator cabinet. The refrigerator is thereby supplied with filtered water to produce ice or to provide chilled water from the refrigerator""s water dispenser.
Because the water filtration apparatus of the present invention is mounted on an exposed, easily accessible, and plainly visible surface of the refrigerator cabinet, the consumer may more readily and easily install the present inventive filter cartridge. In addition, an indicator of filter life may be provided with the present invention which is also readily observable because the apparatus is mounted on the exterior of the refrigerator.
These and other features, aspects and advantages of the present invention will become better understood with reference to the following description and appended claims. The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate an embodiment of the invention and, together with the description, serve to explain the principles of the invention.